Comparative proteome analysis of butachlor-degrading bacteria

A Pseudomonas putida strain, named ER1, was isolated from an agricultural soil and found to actively degrade the herbicide butachlor. The enzyme extracted from ER1 could degrade butachlor. Furthermore, incubation of ER1 in a medium containing 50 mg/kg of butachlor after 3 days resulted in the high butachlor-degrading enzyme activity of ER1. Response of ER1 to butachlor might be related to changes in protein composition at both quantitative and qualitative levels. Total proteins were extracted from control strain (incubated in the medium without butachlor) and the treated strain (incubated in the medium with butachlor). The proteins were separated by two-dimensional gel electrophoresis. Of the total number of ER1 protein, 11 spots were significantly changed under butachlor stress. Analysis by matrix-assisted laser desorption/ionization mass spectrometry and tandem mass spectrometry coupled with database searching allowed the function of some proteins which were similar to the hydrolases activity or oxidoreductase activity.     

除草剂丁草胺对黄鳝的遗传毒性

通过分析红细胞微核、核异常及染色体数目和结构畸变,研究了除草剂丁草胺对黄鳝细胞的遗传毒性。采用腹腔注射的方法染毒,质量分数分别为0. 05、0 .08和0. 12mg/kg,结果(经t检验)表明除草剂丁草胺在较低浓度时( <0. 05mg/kg)基本上不表现诱变性,但0. 12mg/kg浓度组可显著地提高黄鳝外周血红细胞的微核率(P<0 .01),对黄鳝染色体数目畸变率和结构畸变率也有影响(P<0 .01)。这表明除草剂丁草胺在一定浓度范围内对黄鳝具有明显的遗传学损伤作用。     

Combined effects of cadmium and butachlor on soil enzyme activities and microbial community structure

The combined effects of cadmium (Cd, 10 mg/kg of soil) and butachlor (5, 10 and 50 mg/kg of soil) on enzyme activities and microbial community structure were assessed in phaeozem soil. The result showed that phosphatase activities were decreased in soils with Cd (10 mg/kg of soil) alone whereas urease acitivities were unaffected by Cd. Urease and phosphatase activities were significantly reduced by high butachlor concentration (50 mg/kg of soil). When Cd and butachlor concentrations in soils were added at milligram ratio of 2:1 or 1:2, urease and phosphatase activities were decreased, while enzyme activities were greatly improved at the ratio of 1:5. This study indicates that the combined effects of Cd and butachlor on soil urease and phosphatase activities depend largely on the addition concentration ratios to soils. The random amplified polymorphic DNA (RAPD) analysis showed that the changes occurring in RAPD profiles of different treated samples included variation in loss of normal bands and appearance of new bands compared with the control soil. The RAPD fingerprints showed substantial differences between the control and treated soil samples, with apparent changes in the number and size of amplified DNA fragments. The results showed that the addition of high concentration butachlor and the combined applied Cd and butachlor significantly affected the diversity of microbial community. The present results suggest that RAPD analysis in conjunction with other biomarkers such as soil enzyme parameter etc. would prove a powerful ecotoxicological tool.